/*
 * Created on 11-Jan-2005
 * Created by Paul Gardner
 * Copyright (C) Azureus Software, Inc, All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 */

package com.aelitis.azureus.core.dht.router;

/**
 * @author parg
 *
 */

import java.util.List;

public interface DHTRouter {
    public int getK();

    public byte[] getID();

    public boolean isID(byte[] node_id);

    public DHTRouterContact getLocalContact();

    public void setAdapter(DHTRouterAdapter _adapter);

    /**
     * Tells the router to perform its "start of day" functions required to integrate it into the DHT (search for itself, refresh buckets)
     */

    public void seed();

    /**
     * Adds a contact to the router. The contact is not known to be alive (e.g. we've been returned the contact by someone but we've not either got a
     * reply from it, nor has it invoked us.
     * 
     * @param node_id
     * @param attachment
     * @return
     */

    public void contactKnown(byte[] node_id, DHTRouterContactAttachment attachment, boolean force);

    /**
     * Adds a contact to the router and marks it as "known to be alive"
     * 
     * @param node_id
     * @param attachment
     * @return
     */

    public void contactAlive(byte[] node_id, DHTRouterContactAttachment attachment);

    /**
     * Informs the router that an attempt to interact with the contact failed
     * 
     * @param node_id
     * @param attachment
     * @return
     */

    public DHTRouterContact contactDead(byte[] node_id, boolean force);

    public DHTRouterContact findContact(byte[] node_id);

    /**
     * Returns num_to_return or a few more closest contacts, unordered
     */

    public List<DHTRouterContact> findClosestContacts(byte[] node_id, int num_to_return, boolean live_only);

    public void recordLookup(byte[] node_id);

    public boolean requestPing(byte[] node_id);

    public void refreshIdleLeaves(long idle_max);

    public byte[] refreshRandom();

    /**
     * returns a list of best contacts in terms of uptime, best first
     * 
     * @param max
     * @return
     */

    public List<DHTRouterContact> findBestContacts(int max);

    /**
     * Returns a list of DHTRouterContact objects
     * 
     * @return
     */

    public List<DHTRouterContact> getAllContacts();

    public DHTRouterStats getStats();

    public void setSleeping(boolean sleeping);

    public void setSuspended(boolean susp);

    public void destroy();

    public void print();

    /**
     * Adds a routing table observer if it is not already observing.
     * 
     * @param rto
     *            the observer to add
     * @return <code>true</code> if now observing, <code>false</code> otherwise
     */
    public boolean addObserver(DHTRouterObserver rto);

    /**
     * Returns whether the given observer is already observing.
     * 
     * @param rto
     *            the observer to query as observing
     * @return <code>true</code> if observing, <code>false</code> otherwise
     */
    public boolean containsObserver(DHTRouterObserver rto);

    /**
     * Removes the observer if it is already observing.
     * 
     * @param rto
     *            the observer to remove
     * @return <code>true</code> if no longer observing, <code>false</code> otherwise
     */
    public boolean removeObserver(DHTRouterObserver rto);
}
